Tag Archives: École Polytechnique

Here’s a fascinating tale about art and hidden mysteries told at the 245th meeting of the American Chemical Society (ACS) taking place Apr. 7 – 11, 2013, from the Apr. 10, 2013 news release on EurekAlert,

J. Bianca Jackson, Ph.D., who reported on the project, explained that it involved a fresco [located at the Louvre Museum in Paris], which is a mural or painting done on a wall after application of fresh plaster. In a fresco, the artist’s paint seeps into the wet plaster and sets as the plaster dries. The painting becomes part of the wall. The earliest known frescoes date to about 1500 B.C. and were found on the island of Crete in Greece.

“No previous imaging technique, including almost half a dozen commonly used to detect hidden images below paintings, forged signatures of artists and other information not visible on the surface has revealed a lost image in this fresco,” Jackson said. “This opens to door to wider use of the technology in the world of art, and we also used the method to study a Russian religious icon and the walls of a mud hut in one of humanity’s first settlements in what was ancient Turkey.”

Here’s the technology they used to discover the figure hidden in the fresco,

… Termed terahertz spectroscopy, it uses beams of electromagnetic radiation that lie between microwaves, like those used in kitchen ovens, and the infrared rays used in TV remote controls. This radiation is relatively weak, does not damage paintings and does not involve exposure to harmful radiation.

“Terahertz technology has been in use for some time, especially in quality control in the pharmaceutical industry to assure the integrity of pills and capsules, in biomedical imaging and even in homeland security with those whole-body scanners that see beneath clothing at airport security check points,” said Jackson, who is now with the University of Rochester. “But its use in examining artifacts and artworks is relatively new.”

…

The scientists turned to terahertz technology when suspicions surfaced that a hidden image might lie beneath the brushstrokes of a precious 19th century fresco, Trois hommes armés de lances, in the Louvre’s Campana collection. …

To search for a hidden image, Jackson and colleagues, including Gerard Mourou, Ph.D., of Ècole Polytechnique, and Michel Menu, Ph.D., of the Centre de Recherche et de Restauration des Musées de France, and Vincent Detalle, of the Laboratoire Recherche des Monuments Historiques, probed it with terahertz technology. The process is slow, requiring a few hours to analyze a section the size of a sheet of paper.

“We were amazed, and we were delighted,” said Jackson. “We could not believe our eyes as the image materialized on the screen. Underneath the top painting of the folds of a man’s tunic, we saw an eye, a nose and then a mouth appear. We were seeing what likely was part of an ancient Roman fresco, thousands of years old.”

Who is the man in the fresco? An imperial Roman senator? A patrician? A plebian? A great orator? A ruler who changed the course of history? Or just a wealthy, egotistical landowner who wanted to admire his image on the wall?

Jackson is leaving those questions to art historians.

For anyone interested in Campana,

Giampietro Campana was an Italian art collector in the 1800s whose treasures are now on display in museums around the world. When Campana acquired a work of art, he sometimes restored damaged parts or reworked the original. Art historians believe that Campana painted Trois hommes armés de lances after the fresco was removed from its original wall in Italy and entered his collection.

Campana’s practice of restoring and reworking the original was not unusual for the time,

Artists, including some of the great masters, sometimes re-used canvases, wiping out the initial image or covered old paintings with new works. They often did this in order to avoid the expense of buying a new canvas or to enhance colors and shapes in a prior composition. Frescoes likewise got a refresh, especially when the originals faded, owners tired of the image on the wall or property changed hands.

This project was funded in part by CHARISMA [Cultural Heritage Advanced Research Infrastructure; Synergy for a Multidisciplinary Approach to Conservation/Restoration] as part of the European Union’s Framework Programme 7 (FP 7). This project called to mind the NanoForArt FP7 funded project I mentioned in the context of a Mar. 1, 2013 posting about cave art, frescos, and other examples of rock art and how nanotechnology is enabling conservation and restoration.

In any event, it’s nice to find out that those airport scanners are good for something other than delaying your trip and subjecting you and your knickers to inspection.

Québec’s IRSST (Institut de recherche Robert-Sauvé en santé et en sécurité du travail) has issued a May 16, 2012 news release about the results of a study on gloves and nanoparticles,

After developing a sampling protocol and selecting the best analysis and measurement techniques, the research team carried out preliminary tests using four models of nitrile, latex, neoprene and butyl rubber protective gloves and commercial titanium dioxide (TiO2) nanoparticles in powder and colloidal solution form. “The results appear to indicate that powder nanoparticles penetrated the disposable nitrile gloves after seven hours of repeated deformation, while the butyl gloves appeared to be impermeable,” explained investigator Patricia Dolez, the main author of the report. “As for nanoparticles in colloidal solutions, we measured a possibility of penetration through the gloves, in particular when the gloves were subjected to repeated deformation. These preliminary data, which need to be validated by additional studies, show that it is important to continue work in this field.”

…

Based on the results, the research team recommends that care be taken when choosing and using this type of personal protective equipment. “We recommend replacing, at regular intervals, protective gloves that are worn, especially thinner gloves, and gloves that have been exposed to nanoparticles in colloidal solutions,” Dr. Dolez concluded.

ETA June 14, 2012: I should also have mentioned that this was joint project with researchers from the École de technologie supérieure, École Polytechnique, and Université de Montréal were working on this project with the team from IRSST.

They are called therapeutic magnetic microcarriers (TMMC) and they are drug delivery agents which have recently been successfully sent through a living rabbit’s bloodstream to a targeted area for successful administration of a drug. We’re in Fantastic Voyage (for those who don’t know the 1966 movie, it was more notable for then bombshell Raquel Welch’s presence than the science used to shrink a submarine filled with scientists to a microscopic size then injected into a dying diplomat’s bloodstream in an attempt to save his life) territory.

Known for being the world’s first researcher to have guided a magnetic sphere through a living artery, Professor Martel is announcing a spectacular new breakthrough in the field of nanomedicine. Using a magnetic resonance imaging (MRI) system, his team successfully guided microcarriers loaded with a dose of anti-cancer drug through the bloodstream of a living rabbit, right up to a targeted area in the liver, where the drug was successfully administered. This is a medical first that will help improve chemoembolization, a current treatment for liver cancer.

The therapeutic magnetic microcarriers (TMMCs) were developed by Pierre Pouponneau, a PhD candidate under the joint direction of Professors Jean-Christophe Leroux and Martel. These tiny drug-delivery agents, made from biodegradable polymer and measuring 50 micrometers in diameter — just under the breadth of a hair — encapsulate a dose of a therapeutic agent (in this case, doxorubicin) as well as magnetic nanoparticles. Essentially tiny magnets, the nanoparticles are what allow the upgraded MRI system to guide the microcarriers through the blood vessels to the targeted organ. During the experiments, the TMMCs injected into the bloodstream were guided through the hepatic artery to the targeted part of the liver where the drug was progressively released.

Martel’s work was last highlighted here in my April 6, 2010 posting. At that time he was working with bacteria which he and his team had guided into assembling into pyramid shapes. The team had also guided these bacteria through the bloodstream of a rat. There’s more about this earlier work with bacteria in a July 28, 2010 article by Monique Roy-Sole on the Innovation Canada website. As you may have guessed from the ‘pyramids’, Martel’s inspiration for that work came from Egypt,

Martel was inspired by the story of the pyramid of Djoser, built by an estimated 5,000 slaves around 2600 BC, and considered to be the earliest large-scale stone structure known to humankind. He decided to employ 5,000 bacteria in a drop of water as mini workers to construct a similar step pyramid in less than 15 minutes.

As for Martel’s first breakthrough (from Sole’s article),

In 2007, he and researchers from École Polytechnique and the Centre Hospitalier de l’Université de Montréal successfully injected a tiny magnetic device, measuring 1.5 millimetres in diameter, into the carotid artery of a pig, controlling and tracking its travels in the bloodstream with a clinical magnetic resonance imaging (MRI) scanner. Since then, Martel and his team have been working at reducing the size of the device so it can circulate in smaller blood vessels. This would allow doctors to diagnose and treat areas of the body that current instruments, such as catheters, cannot reach.

I hope this proves to be successful. As anyone who’s had a family member or friend undergo cancer treatments knows, the procedures and medicines are crude in that they destroy healthy as well as diseased tissue. Hopefully, this kind of work will make the cures less drastic.